Raised in isolation and largely ignorant of her parents, over time Nemesis concocted a delusion that her mother Kayo, at least, had not abandoned her and was instead just away for long periods of time, inventing occasions where Ma would come by and visit,[2] or even celebrate holidays with her.[3] While periodically waiting for her mother's "return," Nemesis was tormented at least once by the voices of Hänsel and Gretel insisting she'd really been abandoned.[4] Growing up in the forest, she also found herself protected again and again by apparent chance coincidences, unaware that the god in the forest, Michaela, was protecting her.[5]

In EC 970, Nemesis found a small ziz tiama that was really Seth Twiright in a shape-shifted Grim the End and adopted him, believing him to be a Christmas present from her mother. That night, when Seth approached her in a dream, she unwittingly made a contract with him as the Demon of Wrath and became close friends with her new pet "Ziz-san."[3] As she grew older, Nikolay taught Nemesis how to get along alone in the forest, under the guise of being a friend of her frequently absent mother. He also taught her a limited amount of magic, including ice magic as well as how to telepathically communicate with Ziz-san.[5]

By the time she was fourteen, Nemesis joined the Zeus gang in Aceid. In EC 978, when the Zeus member Dio Ames was found murdered, Nemesis and Ziz-san accompanied the gang's leader, Narcissus, to a bar frequented by their rival gang Hades. After they were approached by the bar's owner, the Hades' leader Hardy, Nemesis watched Hardy and Narcissus confront each other. When Hardy prepared to have all of the Hades members gang up on Narcissus, Nemesis, who herself had been grabbed by a member, telepathically commanded Ziz-san to restrain their opponents with his tentacles.

With Hardy at her mercy, Nemesis questioned him over Dio's death; when Hardy denied Hades' involvement in the matter, she had Ziz-san let the members of Hades go and prepared to leave with Narcissus. Just before she did, Hardy added that the wealthy Midas Touch might have been involved in Dio's death. Resolving to investigate later, Nemesis and Narcissus parted ways after leaving the bar and Nemesis took Ziz-san to the Millennium Tree Forest, dropping him off in the Lake of Amusement.

While there, Nemesis visited with Nikolay in his tent, requesting that he look after her pet. After the two discussed Ziz-san for a time, Nemesis talked about Nikolay's current drawing, learning it was of his estranged daughter, until he changed the topic to how he disapproved of her being in Zeus. After brushing off his concerns, Nemesis went home. Three days later, Narcissus called her back to meet with the others at their abandoned factory hideout. There, she and the other members of Zeus watched as Narcissus brought in a man called "Gandhi", who made a deal with them to assassinate Midas Touch while he was sailing back to Elphegort on the S.S. Titanis.

Nemesis greets Ziz-san after sinking the Titanis

After trying and failing to be included in the assassination party, Nemesis chatted with Pan about the upcoming job, among other things. Three days later, Nemesis accompanied some of her fellows to a port to await the return of the assassination party. When the group arrived, Nemesis and the others were horrified to learn that their comrade Remes had been killed, and that Midas had spotted all of their faces and was in prime position to identify them later.

As all of her friends panicked, Nemesis realized what she needed to do and telepathically commanded Ziz-san to sink the S.S. Titanis, killing everyone aboard. After she returned to her shocked friends, the group prepared to leave with the money they obtained; right before she left with them, Nemesis received a doll that Ziz-san had fished from the wreckage. She and the others then returned to the hideout and listened to the radio report on the sinking. Later that year, Nemesis heard Michaela speaking to her through the doll she'd brought back, telling her that a group was coming to capture her and to flee her home.

Realizing she'd been found out, Nemesis listened to the voice's further warnings and then fled,
deciding to go pick up Ziz-san first. As she approached the cave where he was kept, Nemesis ran into Bruno Zero and Shiro Netsuma, who had arrived to arrest her at gunpoint. As she fled to Ziz-san's pool, she ran into Nikolay, who went to meet with her pursuers, and then found to her horror that Ziz-san's pool had been frozen over. Bruno, Shiro, and Nikolay then arrived, and Nemesis was enraged as Nikolay disavowed all ties to her and prepared to turn her in for her crimes. Prevented from fleeing by her former father-figure, Nemesis was brought into custody.[5]

Imprisoned for her crimes, Nemesis fumed over Nikolay's apparent betrayal in jail,[3] before being brought before Gallerian Marlon in court.[6] After she was sentenced, Bruno arranged to save her from prison, giving her the alias "Themis Eight" with the cover story that Nemesis Sudou had perished. For the next three years, Nemesis lived under the care of the espionage organization Bruno headed named PN.[3] During this time, Shiro taught her marksmanship for self-defense;[7] once Nemesis showed proficiency with a gun, she was inducted into PN as an assassin at the age of seventeen, given the codename No. 8. She also deduced that Gallerian Marlon was the "Master" of PN.

Nemesis meets Shakuson under the cherry blossom tree

For her new job, Nemesis was sent to live in an apartment in Rolled, Lucifenia, in EC 982. In spring of that year, she went outside to look at a blooming cherry tree and there she met a man in a police uniform. The two fell to chatting, Nemesis learning that the man was Jakokuese and bonding with him over her shared heritage through Kayo. After further learning that they were both living in the same apartment building, the two introduced themselves, with Nemesis learning that the man was called "Shakuson".

After spending some time together with him, Shakuson flirting with her before returning to work, Nemesis went back to her room and found Bruno waiting for her with Postman. Nemesis received from him a list of her five targets in Lucifenia, a paper giving her a picture and the location of her first target, and a handgun to complete the job with. She was then informed that Postman would deliver her info on her targets alone on subsequent visits,
and that she'd be killed if she refused to complete her missions. Nemesis discussed with Bruno that a police officer was living right above her, and not long after Bruno left.

Nemesis goes to the fireworks festival with Shakuson

Afterwards, Nemesis began killing the targets on her list, assassinating Ghislain Aug, Rodolphe Hugo, and Thabana Johnson. During this time, she also grew close with Shakuson, the two enjoying spending time together. That summer, Nemesis put on a red kimono that allegedly belonged to her mother and went with Shakuson to see the fireworks festival. While she enjoyed the fireworks with her friend, their conversation turned to the murders occurring in Lucifenia, with the police's investigation not turning up much. After spending a little more time together, the two went back inside while Nemesis feared Shakuson learning her secret.

By Autumn, Shakuson had confessed his feelings for her; although conflicted, Nemesis accepted and the two became a couple. After Nemesis killed her fourth target, she returned to her room to find Postman there; after trying and failing to talk with Postman, Nemesis received her new gun and ruminated on her last target, "Nyoze Octo", after Postman left. Not long after, she went up to visit Shakuson and found his room empty; while waiting for him to return, she stumbled on a letter written to him by his brother.

Reading it, Nemesis was shocked to learn that "Shakuson" was Nyoze Octo, a member of the Tasan Party; having been convicted by Gallerian on false charges, he and his fellows planned to take the judge down, and Gammon suggested Nyoze keep an eye on Nemesis for that purpose. After Nemesis finished reading the letter, Shakuson entered the room and Nemesis, overwhelmed, excused herself and went home. She resolved not to tell her superiors that Shakuson was Nyoze, and continued her relationship with him. In the meantime, she watched as more soldiers arrived in Rolled as a result of the war going on in Evillious.[3]

That winter, the end of EC 982, Nemesis walked with Shakuson and the two discussed their holiday plans, agreeing to celebrate Christmas together. Once she'd returned to her room, however, Nemesis found Postman waiting for her with a Naga Custom 44 and instructions to assassinate Shakuson, whose true identity had been discovered. That Christmas, Nemesis met with Shakuson by the cherry tree where they first met. After receiving his Christmas present, a diamond ring and a marriage proposal, Nemesis aimed her gun at Shakuson.

Nemesis listens to Shakuson's final words

As she prepared to fire, and Shakuson commented on how she must have learned his identity, Nemesis confronted him on him seemingly just using her to try and take down the Dark Star Bureau. Nonetheless, she tried to convince him to run away with her; Shakuson refused. In the process of citing the reasons it couldn't work, he revealed to Nemesis that Gallerian Marlon, her "Master", was in fact her true father. After Shakuson comforted her when she became hysterical at this revelation, Nemesis drew back and, filled with sorrow, shot him. She then tried to commit suicide, shooting herself in the temple.

Several minutes later, Nemesis came to in the snow, shocked to have survived. She was greeted by a bespectacled man, who brought her inside to talk. The man, Seth Twiright, explained to her that he was the Demon of Wrath and the true identity of Ziz-san, showing her how Grim the End could shapeshift into a ziz tiama, among other things. He further explained that she had survived her suicide attempt because she was in a contract with him, Nemesis becoming annoyed to hear how he'd tricked her into contracting with him as a child. Once the conversation returned to her desire to die, Seth urged Nemesis to live.

As he transformed Grim the End into a mask and golden bullets, Nemesis listened while he offered her a choice: she could use the bullets to kill the people that were, to her, the most evil, or she could kill herself with them. Eventually, Nemesis decided to not shoot herself, accepting the golden bullets.[3] A day after killing Shakuson, Nemesis fled the country to escape Postman and the police, settling in Retasan. On her fourth morning there, she was drugged and captured by the Tasan Party. Blindfolded and brought to a cell-like room, Nemesis found herself before Nyoze's younger brother, Gammon Octo.[7]

Confronted by the brother of her last victim, Nemesis spoke with Gammon and, as he questioned her, explained that she had gone to Retasan to escape her employers, now hating PN. As Gammon brought up her father being the head of PN, Nemesis asked to confirm this and learned the entire history between the playwright "Kayo Sudou" and Gallerian Marlon, understanding Bruno saved her because she was "Master's" daughter. From there, Gammon discussed the Tasan Party and its goals with Nemesis as he attempted to persuade her to join, particularly their mutual interests in taking down the Dark Star Bureau and ending the war.

Nemesis speaks with Gammon

As they continued to talk, Nemesis learned that Nyoze was the one to learn that she was an assassin for PN. She also discussed with Gammon her youth in Aceid, among other things, as he continually tried to persuade her to join their cause for the sake of "justice" and protecting people. During the conversation, Gammon brought up the letter she'd found from him to Nyoze, revealing that Nyoze had truly loved her and refused Gammon's proposal to use her. As Gammon suggested she take vengeance against people like Gallerian, who had stolen the one she loved from her, Nemesis finally agreed to help the Tasan Party.

Nearly half a year later, Nemesis visited the grave of Shiro Netsuma, who had been murdered by General Tony Ausdin during his massacre at the village of Zenosai. As she paid her respects, she was approached by Gammon and she told him about her relationship to Shiro, agreeing that Gallerian had betrayed her memory by allowing Tony to escape justice. The two then began discussing the progress of the Tasan Party and all the strange occurrences happening in the world, as well as Nemesis ruminating on what she'd learned about her mother's history with Gallerian. Gammon then brought Nemesis away from Shiro's grave, announcing how it was finally time for revolution in the wake of Tony's trial.

By August EC 983, the Tasan Party had instigated the Leviantan Civil War. During the fighting, Nemesis infiltrated the home of General Tony Ausdin while wearing Seth Twiright in his mask form. Attempting to shoot Tony, Nemesis chased him outside of his mansion and found him in the garden with his family. After confronting him for his crimes and surviving his attempt to kill her, Nemesis shot Tony with Shiro's own Naga Custom 44 handgun. She then allowed his family a chance to flee, brushing off Seth's criticism of this. Afterwards, Nemesis went to meet with Gammon and the other militia soldiers at Gallerian's mansion.[7]

Nemesis puts a gun to Gallerian's head

Surprised to find it already burning when she arrived, despite her instructions for her to be allowed to handle Gallerian, Nemesis learned from Seth that Gallerian might have contracted like her and may be responsible for the fire. Soon after, despite Gammon's protests, Nemesis entered the mansion herself to face her father before he died. She soon found Gallerian in his study, flabbergasted to find him talking to a doll and learning that it was the same one she'd had all those years ago, a demonic vessel like Grim the End.

Nemesis then confronted her father, revealing her identity and charging him with all of his evil deeds to the public and to her. Nemesis was soon stunned to learn that Gallerian was never responsible for making her an assassin, and in fact had only known her codename while Bruno handled everything; he also likely didn't know she was his daughter. As her doubts grew with their conversation, Nemesis offered Gallerian a chance to be saved in exchange for his whole fortune. Finding him unable to repent, and incensed to see him doting on "Michelle", the doll, Nemesis shot Gallerian with one of her golden bullets.[8]

After the civil war, Nemesis became a hero to the people and, thanks to the Tasan Party, narrowly avoided being charged with her murder of Tony and Gallerian. After her crimes in Zeus were revealed, however, she was sentenced to ten years imprisonment and spent her twentieth birthday in a jail cell. That night, she spotted Postman watching her in her cell, before the figure disappeared. By EC 989, Gammon Octo had arranged for Nemesis' early release and she rejoined the Tasan Party,[8] becoming elected as its vice leader.

In the meantime, the Tasan Party gained power internationally and in Elphegort in particular.[9] Much later, Gammon Octo disappeared and Nemesis deduced that he had gone to the Millennium Tree Forest, which had by then become known as "Evil's Forest", seeking the Venom Sword that Gallerian had stolen from him. After traveling to Yatski village eleven years after she had last left the forest, Nemesis decided to give Gammon up for dead in light of the rumors about how dangerous the forest had become. After eating at a bar, Nemesis was approached by a servant of Nikolay Tolle, who brought her to Nikolay's mansion on the edge of town.

Meeting with her former caretaker, Nemesis found him bedridden and near death. Nemesis finally spoke with Nikolay over his apparent betrayal of her so many years ago and questioned him over his true reasons for handing her over to Bruno. While they talked, Nikolay apologized for how her friends had all been murdered in prison and offered for her to take her revenge by killing him. Although no longer hating him, Nemesis decided to kill him for both revenge and to give her caretaker a quick death, and shot Nikolay with her Naga Custom 44.[5]

Later, with Gammon missing, Nemesis succeeded him as President of the Tasan Party; by EC 993, the party had gained enough power to take control of the Elphegort government, with Nemesis becoming the country's dictator. Nemesis then ordered Elphegort's army to invade Lucifenia. Sparking a war with the USE, Nemesis immediately allied her nation with Beelzenia and Jakoku, and war spread across the entire world.

With the USE army pushing a two-front offensive upon Elphegort,[9] Nemesis visited the underground laboratory Lunaca Labora seeking a weapon to make Elphegort stronger. With Seth Twiright's reluctant help, Nemesis revived the "boy" of destruction that he had sealed away, which had the power to destroy all of the Third Period. She then presented it to Elphegort's scientists and ordered her military to launch a secret project to develop a weapon based on the "boy": Punishment.[2]

In EC 998, a prototype for Punishment was created and moved to the Millennium Tree Forest for testing. With a golden key in hand, Nemesis inserted it into the black box and fired the weapon, resulting in the entire Millennium Tree Forest being scorched by the blast.[9] A second testing was arranged soon after; although intending to destroy Maistia's western coast, the weapon misfired and destroyed Onigashima instead.[10] With both tests successful, numerous models of Punishment were pointed across the world.[6]

As the conflict continued, Nemesis attended a war meeting with her underlings General Areus Hymn, Gigaty, Polrio, Grand, Mima, and Encheri. As Areus expressed his concern over how poorly Elphegort was doing in the war, Nemesis reassured him by reminding him of Punishment; when Areus gave further doubts over the death toll and potential of misfire, Nemesis claimed that she intended it to be used more as a threat than a first resort. The meeting was then adjourned, and Nemesis returned to her room to do more work. Looking out the window, she saw a commotion with a woman trying to enter the party's headquarters with a cart.

When Polrio came to deliver papers to her, Nemesis discussed the commotion with him; she witnessed the woman reveal a tiger in the cart and watched as the headquarters came under attack from several soldiers, realizing that they were from PN and Maistia. After Polrio delivered her to safety with the other Tasan Party officials, Nemesis stood by as the headquarters and the safe room were invaded, several of her officials becoming injured or killed. As the leader of her attackers attempted to shoot her, Nemesis caused the gun to misfire and injure his hand.

Nemesis disarms Bruno

She then confronted the leader, recognizing him as Bruno Zero, and soon after had him restrained and searched; given a note found on Bruno's person, she learned that someone had leaked information about Punishment to the opposing side. Speaking again with Bruno, Nemesis acknowledged that he had saved her due to being the daughter of someone he loved, and that he was the reason she'd become the woman she was today. Nemesis then shot him, taking her revenge on Bruno once and for all.[10]

The following year, Nemesis visited the site of the destroyed Millennium Tree Forest and found Evil's Theater there, completely intact. Going inside, she entered the room where all of the vessels of sin Gallerian had collected were kept; while there, she was greeted by her mother, "Kayo", who confronted her over using the "boy" of destruction to destroy the forest. Nemesis then related everything that she had done for Elphegort's sake, including killing Bruno. Kayo also brought up Nemesis' murder of Nikolay; during the course of their discussion, Kayo revealed to Nemesis the truth of how she had abandoned her since birth.

Kayo also brought in Postman, and explained how the figure had once been Nikolay's daughter until Ma had turned her into her emotionless servant. While Nemesis was devastated by these revelations, Kayo began strangling her; she revealed she was able to do this due to having six of the Demons of Sin inside her, and planned to absorb the Demon of Wrath from Nemesis after killing her. Kayo was then stabbed by Postman using the Venom Sword, releasing Nemesis.

Realizing Kayo wouldn't die unless killed by a contractor, Nemesis prepared to shoot her own mother, bemoaning how she was unable to save the world and deciding to destroy it instead. As Kayo started to comment on this, Nemesis shot her with Grim the End,[2] killing her and causing her consciousness to secretly take refuge in Postman.[11] After mourning over her mother's corpse, Nemesis returned to the Tasan Party's headquarters. There she fired the Punishment weapon a final time and destroyed all life in the Third Period.[2]

After the destruction of the world, Nemesis' soul was separated from her body and became deluded into thinking she was still Levia, while her body stayed alive due to her contract. As the Third Period merged with the Hellish Yard, the soulless body ended up in the Grave Yard and began to instinctively carry out the last things that she had done before losing her soul: killing Ma and destroying the world.[6] Not long after, Allen Avadonia fetched Nemesis' body and brought her to the delusional Levia, using the body's memories to break the delusion and merge body and soul back together.

With her consciousness restored, Nemesis stood in the ruined world with Allen, Gumillia, Seth, and Michaela, as Allen explained to her the truth of all that had transpired. She then talked to Michaela and Gumillia with Seth, learning how the three had all watched over her and protected her in their respective ways. After talking with her old friends a little longer, Nemesis heard Allen suggest they go to Evil's Theater next to solve some remaining mysteries he had of the world's end. Agreeing to help, Nemesis and her friends set out to save the world.[12]

Splitting up with Gumillia, Michaela, and Seth, Allen and Nemesis trekked towards the site of Evil's Theater. They planned to visit it and then the remains of Lucifenia, with Nemesis hoping to thank Postman, whom she'd realized was an incarnation of Riliane, for saving her life. As they walked, Nemesis began to complain of her fatigue, bantering with Allen about her contract keeping her alive as she stopped to rest. She continued to bicker with him as he pressed her to keep going, before finally relenting, and the two discussed their plans and current situation as they walked.[13]

Eventually the two reached the illusory remains of the Millennium Tree Forest, talking to each other about how it was there despite the real forest being destroyed. Their conversation soon turned to the owner of the Black Box where Allen learned all of his information, Nemesis under the assumption that "Sickle" was really Luna Hazuki. The two continued their conversation, with Nemesis also briefly catching sight of another forest spirit, before Held joined their conversation as a bluebird.

Nemesis spots the Black Box Type S

Held and Nemesis proceeded to banter about her destruction of the world and the nature of "evil"; during the debate, Held directed her attention towards a Type S Black Box in the sky that they should deal with, with the group realizing the box wasn't an illusion like the rest of the world and could potentially do harm. Nemesis and Allen thus resolved to go check it out, particularly as Evil's Theater was underneath it. They then bid Held farewell, Nemesis refusing his offer to go see Levia's old colleagues. During their farewells, Held explained that he became an earth god on the Moon Goddess' will.

As they trekked south, Nemesis and Allen discussed the Moon Goddess, whose identity Nemesis was unsure of. Arriving at the black box, the two watched as Gammon Octo addressed dead soldiers of the Tasan Party and laid blame for the world's end on her and all the other "evil" souls of the world. Hearing Gammon conclude that they must destroy the alleged sources of all evil--that being the demon contractors Banica Conchita, Kayo Sudou, Riliane, Sateriasis Venomania, and Nemesis herself--Allen and Nemesis departed.

Leaving the forest, they discuss what they heard in Gammon's speech as well as speculating about their next move. Determining Gammon intended to use the Black Box Type S against the demon contractors, Nemesis and Allen decide to seek out Seth and Gumillia, Seth being the creator of the Black Box Type S. After talking further, the two eventually decided to head to Lucifenia as they originally planned, in part to talk to Riliane and in hopes of meeting Gumillia there.[14]

Arriving in Lucifenia, Allen and Nemesis found it had become a battleground between the spirits of Lucifenians, and more of the dead Tasan soldiers, with Riliane having already fled. After Nemesis dissuaded Allen from jumping in needlessly to help, the two spotted the Venom Mercenaries nearby and approached them, Allen hiring them to also fight in the battle.

Nemesis shoots down the Black Box

Much later, when the Black Box Type S started to suck up all the souls on the battlefield, Nemesis approached Arth and the other souls left in the palace. After meeting with Arth directly, Nemesis promised to deal with the box and headed to the rooftop. Once there, she carefully took aim and fired at a weak spot in the black box's design, causing the box to malfunction, emit sparks, and crash. With all the souls sucked into it released, Nemesis learned from the freed Kyle Marlon that the box's function was actually "formatting" souls, not sending them elsewhere, meaning it wasn't the kind that Seth made after all.

Internally determining one other person who could have made it besides herself, Nemesis announced she and Allen would go again in search of Riliane and Gumillia. She also suggested going to see Banica as well and argued with Arth against the possibility of also talking to Lich Arklow to help revive the world. With Allen's persuasion, Nemesis finally agreed to try and help in this matter as well, and she and Allen set out first for Beelzenia.[15] Arriving there, the two met with Eater Sabella in his Worldeater form; after they introduced themselves, Eater took them into the mansion.

Meeting with Banica Conchita, Nemesis spoke with her, debating about all that Banica knew of the Second Period from her time as a demon and her knowledge gained from Vlad Tuberci. Not long after, Lich was summoned to the meeting and Nemesis asked him about his intentions in the ended world, relieved to hear that he himself had no intention of trying to revive it. Afterwards, Banica summoned Arte and Pollo and announced her intentions to go to Evil's Theater to stop Gammon. Nemesis soon invited herself along; after Allen was also convinced to join them, the party set once more for the Millennium Tree Forest.[16]

Arriving at Evil's Theater with Banica and her servants, Nemesis and Allen helped engage in battle with the theater inhabitants, Nemesis and Allen dealing with Gammon directly. During their battle, the three of them were interrupted by the irregular twins Adam and Eve. The twins were soon followed by Riliane,[17] who had become possessed by Ma's consciousness inside her and had absorbed all of the demon contractors in the theater.

As Ma attacked them in Riliane's body, the twins Adam and Eve prematurely began their Re_birthday ability to stop her.[11] After Ma escaped the rapidly transforming theater, Nemesis pulled Allen out to safety as well, although forced to leave Gammon behind. After Banica's servants also escaped, the party flew away from the theater on Eater's back. From afar they watched the theater turn into a giant black box, Nemesis explaining to the concerned Allen how it might be "formatting" everyone inside.

Soon after, Nemesis and the others learned the possessed Riliane had also successfully escaped, spotting her on the ground. Appraising the situation, and seeing that Ma threatened to suck all of Evillious into her developing vortex, Nemesis urged Allen to decide between the world or his sister.[18] Allen instead came up with a plan to get Ma out of Riliane first before defeating her, to which Nemesis reluctantly agreed.[19] Touching back down, Eater let Allen off to distract Ma and flew away again with Nemesis.[20]

Reaching the center of the area, while the forest spirits cloaked her presence Nemesis put inscription marks on the ground to boost her power. She then created a tornado that sucked up Allen and Ma; riding on Eater, Nemesis pulled Allen out of the tornado while Ma was still trapped inside. Not long after, the tornado began to weaken from Ma's magic. Ma began flying towards Nemesis and Allen, only to be stopped by Michaela, and soon nearly every soul, singing the Clockwork Lullaby.

During this, the demon Marie flew up to Nemesis and the others with a green onion from Gumillia. Conceiving of a plan, Nemesis used the green onion to request of Gumillia that she have Seth break her demonic contract. She then attempted to pull a body swap on Ma; as Ma resisted the spell and used one on Nemesis in turn, the two struggled until Allen attacked Ma with Grim the End, breaking her control on the contractors inside her.

As Ma's consciousness dispersed, she desperately attacked Nemesis, who swapped her soul into the Clockworker's Doll being held by Riliane. Her soul safe in the doll, Nemesis allowed Ma to take over her body; as Ma fell to the ground, Seth broke Nemesis' contract and her body, as well as Ma, was killed on impact.[19] Later, after Allen and Riliane enacted a Re_birthday to create a new world, Nemesis as Levia became one of the members of the "Evillious" SNS group chat, commenting on the state of the new world.[21]

Following the destruction of the ground world, the mortal realm began merging with the Hellish Yard and all souls of the Heavenly Yard were pulled from the heavenly world into the hellish domain's new land. Shortly after its destruction, the god Sickle prepared to intervene and tasked Allen with meeting some of the souls who had been possessed by the Demons of Sin.[22]

Nemesis was a just, passionate but wrathful woman, blaming others for her own mistakes and directing her anger towards them as a result. Possessing an eye-for-an-eye mentality, Nemesis was quick to take revenge when she saw fit, justifying it as righteous vengeance and holding decades-long grudges. She also took any means to that end, even breaking the law, and reveled in the destruction of her enemies.

This mentality, conversely, made her set on doing things she perceived were ways to atone for her own transgressions, to the point of committing more wrongs to atone for previous wrongs. As part of her atonement for her crimes, Nemesis worked to help Elphegort as its dictator, using the Great War and Punishment in order to save both the country and the entire world.

Due to her true nature as Levia, Nemesis was a HER and desired the destruction of the world, hearing Levia's voice in her mind as part of her condition. Like Levia, she also preferred to escape reality and construct comfortable delusions, as with her perceived familial relationship with Ma. After learning of Ma's true history with her, Nemesis felt betrayed by everyone she knew, having been constantly dependent on someone for most of her life. She thus decided to destroy the world if she couldn't save it, culminating her destructive tendencies. After regaining her past memories as Levia at the world's end, however, Nemesis became more subdued about her actions, although having little regret for them.

As a youth, Nemesis was not above criminal activity, having been a member of Zeus. As part of this, she was loyal to her friends and took extreme measures to protect them, using Ziz-san to sink the S.S. Titanis. As she grew up, Nemesis also hated studying, finding school boring. During her later life, Nemesis also took measures to avoid assassination, and referred to herself in an archaic manner, considering herself Master of the Hellish Yard and Evillious to be hell. With regards to ethnicity, Nemesis considered herself both Elphe and Jakokuese, using her Jakokuese identity to connect with both Ma and Nyoze.

Nemesis was a trained killer and had immense skill with wielding a revolver, although she had skill with other kinds of guns besides.[23] After becoming part of the Tasan Party, Nemesis gained immense political power within the decade. As the dictator of Elphegort, she held absolute power over the nation and its military. Following the development of Punishment, Nemesis was able to freely fire the device at will using the golden key she carried and could potentially wipe out all of the Evillious region with the weapon.[9]

Due to her contract with the Demon of Wrath, Nemesis was unable to be killed by ordinary means, essentially making her immortal. Despite this, the contractor's wounds didn't automatically heal while near the demon's vessel, leaving a serious scar following her suicide attempt. Regardless, she was still able to wield Grim the End, allowing her to use the demon's power to kill other contractors through the vessel; to complement her fighting style, Nemesis transformed the golden key into a bullet for her revolver. Thanks to Hanma, she was also capable of a small amount of magic, specifically telepathic communication and ice magic.[10]

Seth Twiright: Nemesis' pet and partner. Originally knowing Seth as her pet "Ziz-san" and unaware of his true nature, Nemesis bonded with him and the two worked together as beast and master, Nemesis becoming distraught by his "death". Once Seth was revealed as the Demon of Wrath, Nemesis continued to work with him and depend on his abilities, although she became skeptical of whether or not he was really her friend. This skepticism later compounded when her memories as Levia returned.

Levia Barisol: Nemesis' true self. Levia having HER influenced Nemesis subconsciously throughout her life. When the world ended and after her soul was restored to her body, Nemesis came to terms with the fact she was Levia, although continuing to identify as Nemesis for simplicity's sake and in respect to her physical body.

Nyoze Octo: Nemesis' lover. Finding him eccentric but kind, and bonding with him over their shared Jakokuese heritage, Nemesis quickly came to like Nyoze under his alias "Shakuson" and the two became close. Because of this, Nemesis became conflicted by their vast differences in profession and what she saw to be differences in their character, as well as distressed when believing he may have just been using her for the Tasan Party. Nemesis naturally experienced deep regret at his death, longing to have had a happy future with him forever after.

Gallerian Marlon: Nemesis' master, father, and half-brother. Nemesis was originally loyal to Gallerian as the "Master" and followed his every order, although becoming resentful of her work as an assassin and wrathful towards him for her having to kill Nyoze. After learning he was her father, she similarly resented his failure to acknowledge her. Although much of her wrath towards him was mitigated by learning Gallerian was not responsible for the pain he caused her, Nemesis still resented his obvious greed, as well as the love and attention he gave to the Clockworker's Doll instead of her. She ended up killing him without remorse.

Nikolay Tolle: Nemesis' caretaker. Ignorant of Nikolay's past, Nemesis saw him as a friend of her mother's and gradually came to consider him like a father to her. Because of this, she was shocked and enraged by what she perceived as his betrayal, leading to her arrest. Despite her rage, by the time they met again her anger had cooled and Nemesis parted with him on good terms, killing him by his request.

Ma: Nemesis' mother and grandmother. Knowing her as "Kayo Sudou", Nemesis was unable to accept that she had abandoned her and created a delusion of her as a loving albeit often absent mother, constructing entire memories of her giving her gifts for Christmas, teaching her to wear kimonos, and other such things. After learning the truth about "Kayo," Nemesis was devastated and reviled her, killing Ma and resolving to destroy the entire world in the wake of her betrayal.

Nemesis is the goddess in Greek mythology who carried out retribution against those who did evil deeds and obtained undeserved fortunes.

In Roman mythology, "Invidia" is sometimes attributed as the equivalent to the Greek goddess and is the Latin name for the Deadly Sin of Envy; Nemesis' mother, Ma, acts as the replacement for the unawakened vessel of Envy and uses the body and identity of Kayo Sudou.

In Greek mythology, Themis was the female Titan that personified divine order and natural law.

Nemesis' actions leading Elphegort in the Great War parallels many events from World War II, including forming an alliance with Beelzenia and Jakoku similar to the Axis Powers and invading Lucifenia, a country typically inspired by France.

Despite this, Nemesis' manufacturing of Punishment and her initial test of it on Jakoku parallels the United States during the Manhattan Project, with Nemesis saying "Now I am become Death, the destroyer of worlds" as said by scientist J. Robert Oppenheimer; the themes of nuclear warfare are strengthened by the destruction of the First Period, which is also implied to be via nuclear warfare like Nemesis' destruction of the Third Period.

Nemesis' actions in the Leviantan Civil War take place in August, the eighth month of the year, possibly referencing her codename; she also has an "eight-armed" octopus as a pet.

Prior to The Muzzle of Nemesis album being announced, mothy posted a poem entitled "Nemesis" on twitter, seemingly alluding to the events depicted in the album; at the end of the poem, mothy stated it was a late night work and didn't have any meaning.[24]

Nemesis shares several parallels with Gumillia, both having the same representative Vocaloid, Gumi, wielding guns as their preferred weapon, being regarded as Master of the Hellish Yard, and having similar codenames.

Her featured song in the Seven Deadly Sins Series was also uploaded on August 8th; humorously, mothy admitted he had uploaded the song on that date by pure coincidence.[25]

Allen suggests that Nemesis' Elphe appearance despite her parents being Jakokuese and Marlon is due to the world's rules breaking down.[1]